This research is aimed at generating cytotoxic lymphocytes in vitro which can lyse autologous human leukemia and lymphoma cells. Remission lymphocytes will be cultured with X-irradiated lymphocytes pooled from unrelated normal donors or with T-cell growth factor (TCGF). Interferon (IF) or TCGF will be added to the cultures in attempts to augment cytotoxic responses. To determine whether the antileukemic effector cells are cytotoxic T lymphocytes (CTLs) or activated natural killer (NK) cells, we will test the effector cells for cytotoxic activity following treatment with monoclonal antibodies which we have found distinguish CTLs from NK cells. We propose to grow and clone the CTLs in TCGF to determine whether the antileukemia cells are directed against antigens expressed on various patients' leukemia cells. Fresh human lymphocytes will also be treated with IF to determine whether activated NK cells are cytotoxic for autologous and allogenic leukemia and lymphoma cells. In addition, mouse lymphocytes will be stimulated with allogenic normal cells and supernatants from allo-stimulated cultures and tested in vitro and in vivo for antitumor effects.